Citing openly licensed materials, whether they're images or videos or textbooks, is often referred to as "attribution" in the OER world. To "attribute" something, you are giving credit. It's the same idea as "citing" -- just a different term for it.
Always give credit to OER you use/create by adding attribution statements.
The simplest formula for creating attribution statements is TAL: Title, Author, License.
Here's a sample attribution statement:
"Difference between open license, public domain and all rights reserved copyright" by Boyoung Chae is licensed under CC BY 4.0.
Here are the parts of that sample attribution statement:
Title: "Difference between open license, public domain and all rights reserved copyright"
Author: Boyoung Chae
License: CC BY 4.0
How to create attributions:
Open Attribution Builder
Attributing Creative Commons Materials
Coulter Library, Onondaga Community College, Syracuse, NY